Vocabulary
Directions: Scan the following passage and find the words which have roughly the same meanings as those given below. The number in the brackets after each word definition refers to the number of paragraph in which the target word is.

     In the laboratories where astronauts are trained for their journeys, they are subjected to conditions that resemble those of flight. It takes time for them to prepare for the great changes that occur in space. When the spaceship leaves the earth at tremendous speed, the astronauts feel as if they are being crushed against the spaceship floor. Later, when they leave the zone of the earth's gravitation, they are unable to stay in one place. Simple actions, such as eating and drinking, become very difficult to perform. You may get an inkling of what the astronauts have to deal with if you try to drink a glass of water while standing on your head or while just lying down.
     The beginnings of man's conquest of space took place in 1958, seven years before Leonov's trip. The first successful launching of "Sputnik" demonstrated that it was indeed possible to send objects far enough out of range of earth's gravity so that they would not fall back to earth. Rather, such objects could be forced to revolve about the earth, just as the moon does. However, while the moon is so far from earth that it takes it a month to revolve around the earth, man-made satellites, which are closer to earth, can make a complete revolution in a few hours.
     It was three years after the first satellite launching that a spaceship containing a man made a successful flight. The flight lasted less than two hours, but it pointed the way to future developments.
     Other planets are so far away that spaceships must attain tremendous speeds to reach them in a reasonable time. If spaceships were launched from space or from the moon, the absence of weight would permit the ships to be launched with great speed at reduced pressures. A relatively small explosion would be enough to send a ship off at a very fast rate. And since there is no atmosphere in space as there is on earth, the spaceship would meet with no resistance.